Meat-like foodstuff materials have been developed as inexpensive alternatives to animal proteins. Today, meat-like foodstuff materials have received attention again as low-calorie food materials or livestock meat alternative materials for patients with diseases that require them to limit their consumption of animal protein. The conventional techniques concerning such meat-like foodstuffs are described below as examples.
Patent document 1 describes a method for producing a vegetable protein food characterized by mixing:
aggregated tissue-like vegetable proteins having particle sizes ranging from 10 mm to 30 mm;
10 to 40 weight percent of tissue-like vegetable proteins, among which those having maximum particle sizes of less than 10 mm and particle sizes ranging from 1 mm to 5 mm account for at least 70 weight percent of the total amount of such tissue-like vegetable proteins;5 to 40 weight percent of fibrous vegetable proteins with fiber lengths ranging from 5 mm to 30 mm; and a binder, andmolding and coagulating the mixture by heating. Patent document 1 states that a texture analogous to that of natural meat experienced when chewing can be imparted to a food material prepared by incorporating aggregated tissue-like vegetable proteins having particle sizes ranging from 10 mm to 30 mm. Patent document 1 further describes that such aggregated tissue-like vegetable proteins having particle sizes of less than 10 mm make it difficult to obtain a texture analogous to that of natural meat.
Patent document 2 also discloses, as a technique for providing a meat-like food with tissue and a texture analogous to those of one slice of meat such as a slice of steak, a method for producing a meat-like food characterized by mixing a fibrous protein material and a binder with a lump of meat-like protein material obtained by molding either a fibrous protein precursor that becomes fibrous when cooled or a thermoplasticized fibrous protein material into the form of a lump of meat, and then molding the mixture. The above material in the form of a lump of meat has a cross-sectional area of approximately 1 cm2, which is produced by pressurizing and heating with a heat exchanger or the like and then extruding the resultant through an outlet. A meat-like food is formed using a portion of the above material in the form of a lump of meat and a portion in which fibrous proteins are dispersed throughout the binder. Patent document 2 further states that when the “lump” is too small in size, the overall firm texture required for a slice of meat becomes weaker. As in the patent document 3 described below, patent document 2 does not describe the use of a material in the form of a lump of meat after defibration.
Patent document 3 discloses a method for producing a meat-like food, which is characterized by mixing an O/W emulsion, a fibrous protein obtained by kneading a vegetable protein-containing substance with water, applying shearing stress to the mixture while heating it for orientation, and then splitting the resultant; and a binder, and after mixing with the O/W emulsion accounting for 5 to 50 weight percent of the meat-like food, the mixture is molded and heated. According to patent document 3, combining the O/W emulsion with the fibrous protein causes oil to spread throughout the mouth when the meat-like food is chewed, so that a juicy sensation equivalent to that of natural meat can be obtained, and a fibrous texture very similar to that of natural meat can also be obtained.
Patent document 4 describes a bundle of membranous foods having a thin membranous structure, which is obtained by pressurization and heating with the use of a twin-screw extruder. This food contains 0.17 to 0.76 weight percent of starch with respect to 1 part by weight of oil seed protein, and is torn into thin nearly concentric membranes in the extrusion direction when restored to a normal state using hot water. The food described in patent document 4 is intended to be used as an alternative for yuba (bean curd skin). Patent document 4 does not describe the production of any meat-like foodstuff.